Printable View
Hi,
Just wondering what you guys think or do when you come across indoor units the are fed from the outdoor unit and have no local isolation, but the main isolator that has been screwed to the condensing unit on the roof!
Do any of you know of any electrical guidance notes that state that there is the need to have local isolation on an indoor unit?
Hi Cooldude
Whenever i've installed ac units its a matter of good practice to supply an isolator at the indoor unit and also supply the condensate pump with its own permanent power source. I suppose it would depend on the system if its a split or vrv/vrf.
Hi Chillin4alvin
yeah i do aswell but i seem to come across a few during maintenance visits on kit we haven't installed.
I always make a note on the service report of no local isolation on indoor units and that they should have one.
i know that a vrv/vrf indoors will have local isolation, they will be fed via a ring /radial circuit from a fuse board.
but a split/multi split indoor are fed from the condenser (usually) so the regs book dont apply or i cant see it in there to prove that isolation is required. (Mechanical maintenance)
some manufacturers get round it by the on/off button on a wall mount can be used to isolate the system- although it isnt a 2 pole disconnect, and i wouldnt replace an indoor pcb by using the switch
typically isolation should be within arms reach
If I can't get to condenser I just bin the breaker off
The electrical factories act stipulated that where there was a risk of amputation from rotating machinery, there should be a ready means of isolating the electrical supply to the machine. But in 1990 they were replaced by the electricity at work regulations 1989, that now stipulate that isolation by simply switching off is no longer recognised as safe practice. A check has to be made to prove that all poles have disconnected live conductors, and the voltage tester being used has to be proved to be functional by being tested on a known live source before testing the circuit that is going to be worked on, followed by testing the the voltage tester again on a known live source to prove the tester hasn't malfunctioned whilst testing the respective circuit. Then the protective device should be locked off.
Where the protective device can not be turned off and locked in the off position, then a local isolator will need to be installed but having the means to be locked in the off position. After the respective circuit has been proved to be safe, otherwise only a functional operation has been carried out when switching off.
I have a wallmount in my louge and a ducted in the loft.
as it was. A total re build , the drains are all gravity.
still the idea of having a isolator on the wall next to the wall mount,looks terrible and spoils the clean lines of the wall. I have a label in side the filter access cover warning, to isolate from main fuseboard .
if i had trunking and a pump i would of fitted a (at hand) isolator,as it was cluttered with the trunking .